Toy aircraft with pressurized fluid propulsion system

ABSTRACT

A TOY AIRCRAFT HAVING WINGS WHICH PROVIDE LIFT IN COMBINATION WITH AN ENGINE OPERATING ON JET PRINCIPLES. THE PROPULSION ENGINE IS FILLED WITH LIQUID FREON JUST PRIOR TO LAUNCH. THE VAPOR PRESSURE OF THE FREON FORCES FREON IN THE LIQUID STATE FROM THE REAR OF THE ENGINE AND THUS THRUST IS PROVIDED TO THE CRAFT. AS LIQUID IS DISCHARGED THE CENTER OF GRAVITY OF THE PLANE CHANGES CAUSING INTRICATE MANEUVERS TO BE PERFORMED AND REPEATED DIVE AND CLIMB OPERATIONS TO TAKE PLACE. DETAILS OF THE PROPULSION ENGINE ARE PROVIDED.

Oct. 19 1971 c. J. GREEN TOY AIRCRAFT WITH PRESSURIZEDFLUID PROPULSION SYSTEM Filed Jan. 30, 1970 2 Sheets-Sheet 1 INVENTOR. J GREEN Oct. 19, 1971 JIGREEN 3,613,296

TOY AIRCRAFT WITH PRESSURIZED FLUID PROPULSION SYSTEM Filed Jan. 30, 1970 2 Sheets-Sheet 2 INVENTOR. CAM/P155 J G/FEE/Y United States Patent 3,613,296 TOY AIRCRAFT WITH PRESSURIZED FLUID PROPULSION SYSTEM Charles J. Green, Vashon Island, Wash, assignor to Vashon Industries, Inc, Vashon Island, Wash. Filed Jan. 30, 1970, Ser. No. 7,021 Int. Cl. A63h 27/00 US. Cl. 4676 A 18 Claims ABSTRACT OF THE DISCLOSURE A toy aircraft having wings which provide lift in combination with an engine operating on jet principles. The propulsion engine is filled with liquid Freon just prior to launch. The vapor pressure of the Freon forces Freon in the liquid state from the rear of the engine and thus thrust is provided to the craft. As liquid is discharged the center of gravity of the plane changes causing intricate maneuvers to be performed and repeated dive and climb operations to take place. Details of the propulsion engine are provided.

Various types of toy airplanes have been devised over the years. With the advent of jet aircraft it would be advantageous to have a toy aircraft which would actually fly and which operated on true jet principles. It is thus an object of the present invention to provide such a toy aircraft.

Another object of the present invention is to provide a toy aircraft having a jet engine which is easily and safely recharged through the use of a simple loading system.

Another object of the present invention is to provide an engine for a toy aircraft which uses Freon and wherein the engine is completely re-fillable.

An additional object of the present invention is to provide a toy aircraft having a re-fuelable non-pyrogenic jet engine and which undergoes interesting maneuvers due to changes in its center of gravity as the fuel supply is depleted.

In accordance with the teachings of the present invention a lightweight toy aircraft is provided with a central axial opening adapted to receive and hold a tubular jet engine. The engine itself is provided with a venting opening at the forward end and a discharge opening at the rear end. The engine is adapted to be filled through the rear opening with an appropriate liquid such as Freon. When the engine is completely filled with Freon and the plane is launched the plane goes into a climbing mode. The thrust of the engine will not continually sustain the climb and therefore the plane either stalls or falls-off from the climb attitude and starts into a dive. As the plane goes into a dive the liquid runs forward causing the dive to be accentuated and the speed increases. Due to the increased speed the lift provided by the wings is increased and the plane starts to pull out of the dive. As it does so the center of gravity again shifts to the rear and the climb mode is again repeated. This action continues until the fuel supply is exhausted and the plane then goes into a glide mode due to the location of the center of gravity no longer being changed by moving liquid.

The above and additional advantages and objects will be further understood from the following description when read with reference to the accompanying drawings.

FIG. 1 is a perspective view showing the plane and the fueling assembly.

FIG. 2 is a cross-sectional view showing the engine as it is being refueled.

Patented Oct. 19, 1971 FIG. 3 is a cross-sectional view showing the engine during operation.

FIG. 4 is a side view partially in cross section showing the plane in a climb attitude with the center of gravity shifted rearwardly.

FIG. 5 is a side view partially in cross section showing the plane in its dive mode with the center of gravity shifted forwardly.

Turning now to the drawings there is illustrated in FIG. 1 a toy aircraft 10 having a body 11 and wings 12. The aircraft is preferably made of a lightweight material such as Styrofoam with the wings being properly shaped to provide lift to the aircraft when an appropriate speed is achieved. Located in an elongated central axial cavity of the body 11 is a jet engine 13 having an exhaust nozzle 14 adapted to mate with the end 15 on the filling nozzle 16 which is secured to the end of the filling hose 17. The filling hose 17 extends to the can of propulsion fluid 18 which is preferably Freon 12. As seen by the dotted line the lower end 17A of the filler hose 17 extends to a point near the bottom of the can 18 so that the vapor pressure of the Freon 12 will force liquid Freon 12 up the hose 17 where it will be discharged into the engine under the control of the pushbutton valve assembly 20.

As seen in FIG. 2 the engine 13 is comprised primarily of an elongated tubular aluminum cylinder 25 having a front end cap 26 which is provided with a venting hole 27. A vent control in the form of a paper disc 28 is held in position across the opening 27 so that the escape of Freon 12 gas is controlled and also in order to prevent the escape of liquid Freon 12. when the plane is in its dive mode. A small Washer can be used to hold the paper disc 28 in position across the vent opening 27.

The discharge nozzle 14 will be seen to be held in the opposite end of the cylinder 25 due to the crimping of the end of the cylinder over the body of the discharge nozzle. The discharge opening 30 is used for filling of the engine and thus as seen in FIG. 2 the tip 15 of the filling nozzle is inserted into the discharge nozzle 14 where the end of the filler pipe will be aligned with the discharge opening 30.

Since the engine is provided with the vent opening 27 there will always be less pressure in the engine than in the supply can 18 and hence the vapor pressure in the supply can 18 will be able to force liquid into the body of the engine. It is also of importance tonote that the vent opening 27 permits complete filling of the engine since the air which would be in the engine when the engine is empty is able to escape through the vent opening 2.7 as the filling operation occurs. .In practice the user inserts the tip 15 into the discharge nozzle 14 and depresses the button 20 so that the vapor pressure in the can 18 will force the liquid Freon 12 into the engine and displace the air which at that time fills the engine.

When the engine has been completely filled the operator will note a change in the hissing sound which takes place as the engine is being filled and will also 'observe that liquid no longer flows through the hose 17 (clear tubing being used for this purpose). The filler tube is then quickly removed from the rear end of the engine and the plane is launched by hand in the same manner as any other hand-thrown toy aircraft. The vapor pressure in the engine immediately forces liquid from the discharge nozzle 15 in the manner illustrated in FIG. 3. In practice it is found that the fluid being discharged is approximately 30% gas and liquid which provides excellent thrust characteristics.

Due to the forward thrust provided by the engine the wings give lift to the plane and in addition it will be seen in FIG. 3 that as the liquid is discharged the center of gravity of the plane moves rearwardly. This is illustrated in FIG. 4 where the center of gravity is indicated at 35 when the engine is filled with liquid and has moved to position 36 as soon as a portion of the liquid has been discharged. Since the center of gravity of the plane-engine combination has moved rearwardly the rear of the plane drops and the plane goes into a rather steep climb. However the thrust of the engine is not adequate to continue the steep climb and the plane soon falls-off. As soon as it falls-off from the climb mode the liquid rushes to the front of the engine causing the center of gravity to move forwardly and the plane goes into a dive. As seen in FIG. 5 the center of gravity is at some point 37 which is forward of the point 35. As the dive takes place the speed increases, the lift provided by the wings increases, and hence it is found that the plane starts to pull out of the drive. As soon as the plane starts to pull out of the dive the liquid again rushes to the rear of the engine, the center of gravity shifts rearward, added thrust is provided since the engine now exhausts liquid, and the above described climb mode is repeated. As illustrated in FIG. 5 the engine exhausts primarily gas during the dive mode and hence fuel is conserved during the time when maximum thrust is not required.

It is of importance to note that the center of gravity is at location 35 when the engine is empty. This point is so located relative to the center of pressure of the wings that a substantially flat glide is achieved When the engine is empty. Therefore when the fuel supply has been exhausted the plane simply glides back to earth in a smooth flight since the center of gravity no longer shifts.

The size of the engine will of course vary in accordance with the particular aircraft to be flown. One toy aircraft having an overall length of approximately 12 inches, at wingspan of about 11 inches, and made from Styrofoam with a design such as illustrated in FIG. 1 was found to undergo the above-described flight characteristics using an engine with an outside diameter of approximately /8 inch and a length of approximately 4% inches. By using low cost aluminum tubing as the body for the engine and simple aluminum end caps it has been found that the entire engine assembly can be manufactured at a very low cost. The vent cover 28 can be any suitable material which permits air to escape as the filling operation takes place, and yet prevents free-flow of the liquid through the vent. Conventional 25% cotton ledger paper such as that marketed under the name Fox River Ledger works well in that it provides a low leak rate. The engine itself is simply held in the airplane body by friction, the fit being such that the air and gas escaping through the vent opening can escape around the engine body.

There has thus been disclosed a novel toy aircraft and simple jet engine for propelling the same. While the invention has been disclosed by reference to a presently preferred embodiment it will be recognized that changes can be made in various details without departing from the inventive concepts.

What is claimed is:

1. A toy aircraft comprising in combination: an airframe including airfoil means; and engine means carried by said airframe comprising a rgid, substantally non-expansible, hollow member adapted to be filled with a selfpressurizing liquid, said hollow member having a vent opening at the forward end thereof and a discharge opening at the rear end thereof, said discharge opening communicating directly with the rear portion of the interior of said hollow member, and said hollow member being so located in said airframe as to provide the aircraft with a center of gravity substantially in line with the center of pressure of said airfoil means when said hollow member is empty.

2. The aircraft of claim 1 wherein said airfoil means comprises wings having airfoil sections.

3. The aircraft of claim 1 wherein said hollow member Comprises an elongated tubular member having each end thereof closed by end-caps having said vent opening and said discharge opening therein; and vent control means disposed across said vent opening and adapted to permit leakage of air from said tubular member and substantially to prevent leakage of said liquid therefrom.

4. The aircraft of claim 2 including a vent control means disposed across said vent opening and adapted to permit leakage of air from said hollow member and substantially to prevent leakage of said liquid therefrom.

5. The aircraft of claim 4 wherein said vent control means comprises a piece of material previous to air and substantially impervious to said liquid.

6. The aircraft of claim 5 wherein said material is pa er.

7. The aircraft of claim 5 wherein said piece of material is a paper disk.

8. A propulsion engine for a model vehicle comprising in combination a container for receiving and holding a selfpressurizing propulsion liquid, said container having a forward end and a rearward end, a venting means disposed in said forward end and adapted to permit leakage of air from said container and substantially to prevent leakage of said liquid therefrom, and a discharge nozzle means including an opening therein disposed in said rearward end, whereby said container can be completely filled with said liquid through said opening.

9. The engine of claim 8 wherein said nozzle means communicates directly with the adjacent portion of the interior of said container.

10. The engine of claim 8 wherein said venting means comprises a piece of material pervious to air and substantially imperivous to said liquid.

11. The engine of claim 10 wherein said material is paper.

12. The engine of claim 10 wherein said piece of material is a paper disk.

113. The engine of claim 8 wherein said container is a rigid, substantially non-expensible, elongated right circular cylinder.

14. The engine of claim 13 wherein said nozzle means communicates directly with the adjacent portion of the interior of said container.

115. The engine of claim 14 wherein said venting means comprises a piece of material pervious to air and substantially impervious to said liquid.

16. The engine of claim 15 wherein said material is paper.

117. The engine of claim 15 wherein said piece of material is a paper disk.

18. An engine for toy vehicles adapted for use with a self-pressurizing liquid comprising: a rigid, substantially non-expensible, right circular cylindrical body member having first and second open ends; a nozzle member secured to said body member across said first open end and including means defining a discharge passage communicating with the interior of said body member; a vent member secured to said body member across said second open end, said vent member having a vent opening therein extending from the interor of said body member to the exterior thereof and a vent control member positioned across said opening, said vent control member being of a material which substantially prevents the passage of said liquid through said vent opening and permits the passage of air therethrough.

References Cited UNITED STATES PATENTS 3,229,417 1/1966 Stanzel 4676 A 3,232,001 2/1966 Stanzel 4676 A 2,410,682 11/1946 Richardson 4676 A 2,943,417 7/1960 Greenspan et al. 4676 A ROBERT PESHOCK, Primary Examiner UNITED STATES PATENT OFFICE (5 6Q) CERTIFICATE OF CORRECTION Patent No. 3, 613, 296 Dated October l9 197].

Inventor(s) Charles J. Green It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1, line 58, "rgid, 'substantally" should read rigid, substantially Claim 5, line 10, "previous" should read pervious Claim 10, line 31, "imperivous" should read impervious Claim 13, line 37, "non-expensible" should read non-exPansihle- Claim 18, line 51, "non-expensible" should read non-expansible Signed and sealed this 16th day of May 1972.

(SEAL) Attest:

EDWARD M.F'LEI'CHER,JR. ROBERT GOT'I'SCHALK Attesting Officer" 7 Commissioner of Patents 

